Automatic lamp control circuits are well known. Typically, a control circuit utilizes a photosensor to sense the ambient light level. The circuit turns the lamp on at night and off during the day. Such automatic control circuits are particularly useful for nightlights, outdoor lights such as street lights, and for lamps that are in inaccessible locations.
Prior art automatic lamp control circuits have had two basic configurations. In one configuration, the control circuit is a separate unit, and modification of the existing wiring to the lamp socket is required for installation. In the other configuration, the control circuit is contained in an adaptor which is mounted between the lamp socket and the lamp. The adaptor includes a plug for connection to the lamp socket and a socket for receiving the bulb. While such configurations are generally acceptable in operation, they entail the inconvenience and expense of separate units for light control. In many cases, the resulting combination is too large to fit into a fixture designed for the lamp.
A circuit for automatic control of a nightlight is disclosed in U.S. Pat. No. 4,588,926 issued May 13, 1986 to Pezzolo. The Pezzolo patent discloses a collar for mounting of a photocell and a printed circuit board. The collar slips over the base of a lamp and is attached around the neck of the bulb. Because the collar is external to the lamp, an adaptor is required to implement the disclosed circuit. A nightlight utilizing an adaptor which apparently includes a photosensor control circuit is disclosed in Design Patent No. 288,967 issued Mar. 24, 1987 to Naft.
It is a general object of the present invention to provide a lamp assembly with an integral automatic control circuit.
It is another object of the present invention to provide a lamp having a light control circuit mounted in the base thereof so that the lamp can be installed and operated in a conventional lamp socket.
It is a further object of the present invention to provide an automatically controlled lamp which is simple in construction and easy to use.